Central Lymph Node Dissection in Differentiated Thyroid Cancer

Endoscopic thyroidectomy for central lymph node dissection-is there a difference in the number of lymph node dissections performed through different surgical approaches? A retrospective cohort study and pooled data research

BACKGROUND

Endoscopic thyroidectomies are commonly performed for thyroid cancer. Previous studies indicated that trans-areola approach is inferior in central lymph node dissection (CLND) due to clavicle protruding. The present study aimed to compare different surgical approaches of endoscopic thyroidectomies regarding surgical outcomes.

METHODS

Retrospective analysis of 153 patients underwent endoscopic thyroidectomies through oral and areola approaches from Nov. 2019 to Dec. 2022 in our institution, baseline information, surgical outcomes and postoperative complications were recorded and analyzed. For pooled data analysis, comprehensive searching was done to identify studies concerning comparison of endoscopic thyroidectomies. Basic information and surgical outcomes were extracted. RevMan 5.4 was used to analyze the pooled data. p < 0.05 was considered statistically different.

RESULTS

A total of 153 patients were included with 75 in oral, 78 in areola. The operative time was longer in oral compared with other two groups. Number of lymph nodes, positive lymph nodes, hospital stay, postoperative drainage and complications were not different between the two groups. For the systematic review, five studies of oral and areola comparisons containing 568 patients was finally included in the meta-analysis. The operative time was slightly longer in oral group. Number of positive lymph nodes were slightly larger in areola. The blood loss, lymph nodes, hospital stay and transient hoarseness were not different between oral and areola.

CONCLUSIONS

Oral demanded more operative time than other approaches. Lymph nodes, positive lymph nodes and hospital stay were similar between different groups. Areola was comparable with oral in lymph nodes and positive lymph nodes.

Impedance-based detection of cervical lymph-node involvement in thyroid cancer patients: a human model study

PURPOSE

Current diagnostic modalities for differentiating between benign and malignant cervical lymph nodes in patients with thyroid cancer are imprecise and time-consuming. The real-time intraoperative detection of malignancy in suspicious lesions could improve the medical management of these patients. This human study was undertaken to evaluate a precise, newly developed Electrical Lymph-Node Scanning (ELS) system to facilitate the effective treatment of cervical LNs in thyroid cancer patients.

METHODS

Using the ELS, we examined a collective 109 radiologically suspicious lymph nodes from 36 patients after dissection and compared the ELS results with the histopathological findings.

RESULTS

A total of 27 involved lymph nodes were correctly diagnosed, while 75 reactive or free lymph nodes were correctly identified as uninvolved lymph nodes by ELS (as 3 false negatives and 4 false positives) with total sensitivity and specificity of 90% and 94.9%, respectively. The corresponding negative and positive predictive values were 87.1% and 96.2%, respectively.

CONCLUSIONS

Results from this clinical study demonstrate the value of the ELS as a surgical assist adjunct for differentiating equivocal lesions during neck dissection surgery for patients with different types of thyroid cancer.

Prophylactic central neck dissection in differentiated thyroid cancer: risks and benefits in a population with a high rate of tumor recurrence

BACKGROUND

The role of prophylactic central neck dissection (pCND) in differentiated thyroid cancer (DTC) is still controversial.

METHODS

In a cohort of 274 DTC cN0 patients with a high rate of tumor recurrence, who underwent total thyroidectomy with or without pCND, clinical and histopathological features were retrospectively analyzed.

RESULTS

In our cohort, no clinical or histopathological features are able to predict the presence of central lymph node metastases (CLNM) at diagnosis, which instead represents the only variable significantly associated with a higher risk of long-term tumor relapse, independently from age, sex, BMI and radioiodine treatment (OR=1.03, 95% CI: 1.002-1.074, P<0.05). Moreover, our study demonstrates that pCND does not significantly increase the risk of post-surgical complications.

CONCLUSIONS

In our setting, pCND could have a key role in the management of DTC. The risks and benefits of pCND should be evaluated for each population to make the most appropriate therapeutic choice.

Multimodal separation and cross fusion network based on Raman spectroscopy and FTIR spectroscopy for diagnosis of thyroid malignant tumor metastasis

The diagnosis of cervical lymph node metastasis from thyroid cancer is an essential stage in the progression of thyroid cancer. The metastasis of cervical lymph nodes directly affects the prognosis and survival rate of patients. Therefore, timely and early diagnosis is crucial for effective treatment and can significantly improve patients' survival rate and quality of life. Traditional diagnostic methods, such as ultrasonography and radionuclide scanning, have limitations, such as complex operations and high missed diagnosis rates. Raman spectroscopy and FTIR spectroscopy can well reflect the molecular information of samples, have characteristics such as sensitivity and specificity, and are simple to operate. They have been widely used in clinical research in recent years. With the development of intelligent medical diagnosis technology, medical data shows a multi-modal trend. Compared with single-modal data, multi-modal data fusion can achieve complementary information, provide more comprehensive and valuable diagnostic information, significantly enhance the richness of data features, and improve the modeling effect of the model, helping to achieve better results. Accurate disease diagnosis. Existing research mostly uses cascade processing, ignoring the important correlations between multi-modal data, and at the same time not making full use of the intra-modal relationships that are also beneficial to prediction. We developed a new multi-modal separation cross-fusion network (MSCNet) based on deep learning technology. This network fully captures the complementary information between and within modalities through the feature separation module and feature cross-fusion module and effectively integrates Raman spectrum and FTIR spectrum data to diagnose thyroid cancer cervical lymph node metastasis accurately. The test results on the serum vibrational spectrum data set of 99 cases of cervical lymph node metastasis showed that the accuracy and AUC of a single Raman spectrum reached 63.63% and 63.78% respectively, and the accuracy and AUC of a single FTIR spectrum reached 95.84% respectively and 96%. The accuracy and AUC of Raman spectroscopy combined with FTIR spectroscopy reached 97.95% and 98% respectively, which is better than existing diagnostic technology. The omics correlation verification obtained correlation pairs of 5 Raman frequency shifts and 84 infrared spectral bands. This study provides new ideas and methods for the early diagnosis of cervical lymph node metastasis of thyroid cancer.

Evaluation and Surgical Management of Multiple Endocrine Neoplasias

Multiple endocrine neoplasia (MEN) syndromes are rare autosomal dominant diseases that are associated with a mixture of both endocrine and non-endocrine tumors. Traditionally, there are 2 types of MEN that have unique clinical associations: MEN 1 (parathyroid hyperplasia, pancreatic neuroendocrine tumors, and pituitary tumors) and MEN 2 (medullary thyroid carcinoma and pheochromocytoma), which is further classified into MEN 2A (adds parathyroid adenomas) and 2B (adds ganglioneuromas and marfanoid habitus). Many of the endocrine tumors are resected surgically, and the pre, intra, and postoperative management strategies used must take into account the high recurrence rates asscioated with MEN tumors.

Cost-Effectiveness of Parathyroid Cryopreservation and Autotransplantation

Importance

Delayed autotransplantation of cryopreserved parathyroid tissue (DACP) is the only surgical treatment for permanent postoperative hypoparathyroidism. Studies suggest that only a small minority of cryopreserved samples are ultimately autotransplanted with highly variable outcomes. For these reasons, many have questioned the economic utility of the process, although, to the authors' knowledge, this has never been formally studied.

Objective

To report the clinical outcomes of parathyroid cryopreservation and DACP at a large academic institution and to determine the cost-effectiveness of this treatment.

Design, Setting, and Participants

An institutional review board-approved, retrospective review of patients at a single institution who underwent DACP over a 17-year period was conducted with a median follow-up of 48.2 months. A forward-looking cost-utility analysis was then performed to determine the economic utility of cryopreservation/DACP vs usual care (monitoring and supplementation). Patients who had parathyroid tissue in cryopreserved storage between August 2005 to September 2022 at a single-center, academic, quaternary care center were identified.

Exposure

Parathyroid cryopreservation and DACP.

Main Outcomes and Measures

Graft functionality, clinical outcomes, and cost utility using a willingness-to-pay threshold of $100 000 per quality-adjusted life-year (QALY).

Results

A total of 591 patients underwent cryopreservation. Of these, 10 patients (1.7%; mean [SD] age, 45.6 [17.9] years; 6 male [60%]) underwent DACP. A minority of autografts (2 [20%]) were subsequently fully functional, one-half (5 [50%]) were partially functional, and 3 (30%) were not functional. The cost-utility model estimated that at a large academic center over 10 years, the additional cost of 591 patients undergoing cryopreservation and 10 patients undergoing autotransplantation would be $618 791.64 (2022 dollars) and would add 8.75 QALYs, resulting in a cost per marginal QALY of $70 719.04, which is less than the common willingness-to-pay threshold of $100 000/QALY.

Conclusions and Relevance

The reimplantation rate of cryopreserved tissue was low (<2%), but when implanted, autografts were at least partially functional 70% of the time. In the first-ever, to the authors' knowledge, formal cost analysis for this treatment, results of the current model suggest that cryopreservation and autotransplantation were cost-effective compared with the usual care for hypoparathyroidism at a large, academic institution. It is recommended that each surgical center consider whether the economic and logistical commitments necessary for cryopreservation are worthwhile for their individual needs.

An integrated model incorporating deep learning, hand-crafted radiomics and clinical and US features to diagnose central lymph node metastasis in patients with papillary thyroid cancer

OBJECTIVE

To evaluate the value of an integrated model incorporating deep learning (DL), hand-crafted radiomics and clinical and US imaging features for diagnosing central lymph node metastasis (CLNM) in patients with papillary thyroid cancer (PTC).

METHODS

This retrospective study reviewed 613 patients with clinicopathologically confirmed PTC from two institutions. The DL model and hand-crafted radiomics model were developed using primary lesion images and then integrated with clinical and US features selected by multivariate analysis to generate an integrated model. The performance was compared with junior and senior radiologists on the independent test set. SHapley Additive exPlanations (SHAP) plot and Gradient-weighted Class Activation Mapping (Grad-CAM) were used for the visualized explanation of the model.

RESULTS

The integrated model yielded the best performance with an AUC of 0.841. surpassing that of the hand-crafted radiomics model (0.706, p < 0.001) and the DL model (0.819, p = 0.26). Compared to junior and senior radiologists, the integrated model reduced the missed CLNM rate from 57.89% and 44.74-27.63%, and decreased the rate of unnecessary central lymph node dissection (CLND) from 29.87% and 27.27-18.18%, respectively. SHAP analysis revealed that the DL features played a primary role in the diagnosis of CLNM, while clinical and US features (such as extrathyroidal extension, tumour size, age, gender, and multifocality) provided additional support. Grad-CAM indicated that the model exhibited a stronger focus on thyroid capsule in patients with CLNM.

CONCLUSION

Integrated model can effectively decrease the incidence of missed CLNM and unnecessary CLND. The application of the integrated model can help improve the acceptance of AI-assisted US diagnosis among radiologists.

PAFAH1B3 Regulates Papillary Thyroid Carcinoma Cell Proliferation and Metastasis by Affecting the EMT

INTRODUCTION

Thyroid carcinoma (TC) is currently the prevalent type of endocrine malignancy worldwide, having an incidence of around 15.5 per 100,000 people. However, the underlying mechanisms of TC tumorigenesis remain to be further elucidated.

METHODS

Performing the database analyses, Platelet-activating factor acetylhydrolase 1B3 (PAFAH1B3) was found to be dysregulated in several carcinomas and might trigger tumor occurrence as well as the progression of TC. Clinicopathological information of patients from our local validated cohort and The Cancer Genome Atlas (TCGA) cohort also confirmed this hypothesis.

RESULTS

Our present research showed that elevated expression of PAFAH1B3 has a close association with worse behavior in papillary thyroid carcinoma (PTC). We utilized the small interfering RNA to obtain the PAFAH1B3-transfected PTC cell lines, including BCPAP, FTC-133, and TPC-1, and then further examined their biological function in vitro. Furthermore, gene set enrichment analysis suggested that PAFAH1B3 is implicated with epithelial-mesenchymal transition (EMT). Afterward, the western blotting assays aimed at EMT-related proteins were performed.

CONCLUSION

In short, our results revealed that silencing PAFAH1B3 could hinder the capabilities of proliferation, migration, and invasion of PTC cells. Increasing expression of PAFAH1B3 might be of quintessence with lymph node metastasis by triggering EMT in PTC patients.

Long-term impact of prophylactic central neck dissection in non-invasive classic papillary thyroid carcinoma

BACKGROUND

The utilization of prophylactic central neck dissection (pCND) in cases of non-invasive clinical node-negative (cN0) papillary thyroid carcinoma (PTC) remains a topic of debate, with a dearth of long-term evidence.

MATERIALS AND METHODS

We retrospectively reviewed 1181 cN0 PTC patients from 1997 to 2011. Of these, 641 underwent pCND (pCND + group) and 540 did not (pCND-group). Propensity score matching (PSM) was used to identify similar patients. Event-free survival and long-term complications including permanent hyperparathyroidism and permanent recurrent laryngeal nerve (RLN) paralysis were analyzed after PSM.

RESULTS

The pCND + group had more aggressive characteristics. In the matched cohort after PSM, the 5-year, 10-year, and 15-year EFS rates were 98.9 %, 98.2 %, and 97.1 % for the pCND + group, and 97.7 %, 97.1 %, and 97.1 % for the pCND-group, respectively. There was no statistically significant difference in EFS rates between the two groups (Log Rank P = 0.38). There was no statistically significant difference in the incidence of permanent hyperparathyroidism (3.3 % vs. 1.5 %, P = 0.08) and permanent RLN paralysis (1.7 % vs. 0.9 %, P = 0.13) between the pCND+ and pCND- groups.

CONCLUSION

Our study, with a median follow-up duration of 107 months, indicates that pCND does not lead to a significant reduction in nodal recurrence among non-invasive cN0 PTC patients.

Study to Evaluate the Pattern of Nodal Distribution in Papillary Thyroid Cancer

Among the thyroid cancers, papillary thyroid cancer (PTC) is the most common with lymphatic metastasis. It has the propensity to spread to the level II-VI lymph nodes in a predictable manner. We evaluated the pattern of nodal distribution at different levels of neck in papillary thyroid cancer in this Observational Prospective study. Total 41 patients of PTC (Papillary thyroid cancer) were included in the study. 36 out of them were diagnosed as PTC by FNAC and underwent total thyroidectomy and central neck dissection, while 5 patients were histologically confirmed cases of PTC on previous hemithyroidectomy and underwent completion thyroidectomy and central neck dissection .Patients with T3/T4 stage or N1 underwent lateral neck dissection also. Clinicopathological factors such as age, sex, tumor stage, nodal metastasis and extracapsular invasion, were evaluated. Lymph node metastasis was noted in 21 patients (51.2%) and all these patients had central (level VI) lymph node involvement. Among 21 patients, pathological ipsilateral lateral neck metastasis was noted in 6 patients (28.57%) at level II, 10 patients (47.62%) at level III and 8 patients (38.10%) at level IV. Only 5 patients (23.81%) had metastasis at level V. Extracapsular invasion was observed in 10 (24.4%) patients. We concluded that patients with PTC show higher rates of metastasis at central neck (level VI) and are not easily detected on clinical examination or by USG due to low sensitivity but are sensitive and specific for lateral neck nodes in late stages . Thus, ipsilateral selective neck dissection should be considered with total thyroidectomy and central neck dissection in presence of clinically or radiologically evident lateral lymph nodes (preoperatively) and in T3, T4 stage (late stages) tumors.

Postoperative hypoparathyroidism after thyroid operation and exploration of permanent hypoparathyroidism evaluation

Background

To investigate the risk factors for hypoparathyroidism, discuss the prevention of postoperative hypoparathyroidism, and explore permanent postoperative hypoparathyroidism evaluation (PPHE).

Methods

A total of 2,903 patients with thyroid nodules were treated between October 2012 and August 2015. Serum calcium and intact parathyroid hormone (iPTH) levels were measured at 1 day, 1 month, and 6 months postoperatively. The incidence and management of hypoparathyroidism were analyzed. The PPHE was established based on the risk factors and clinical practice.

Results

A total of 637 (21.94%) patients developed hypoparathyroidism, and 92.15% of them had malignant nodules. The incidence rates of transient and permanent hypoparathyroidism were 11.47% and 10.47%, respectively. The iPTH level was lower in patients with malignant nodules who underwent total thyroidectomy (TT) and central-compartment neck dissection (CND). These factors were independently associated with the recovery rate of parathyroid function. The formula for PPHE is as follows: {iPTH} + {sCa} + {surgical procedure} + {reoperation} + {pathologic type}. A scoring system was developed, and we scored low, middle, and high risk of permanent postoperative hypoparathyroidism as 4-6, 7-9, and 10-13, respectively. The differences in the recovery rates of parathyroid function in several risk groups were statistically significant (p < 0.001).

Conclusion

Simultaneous TT and CND is a risk factor for hypoparathyroidism. The reoperation is not associated with hypoparathyroidism. Identification of parathyroid glands in situ and preservation of their vascular pedicles are key factors in managing hypoparathyroidism. PPHE can forecast the risk of permanent postoperative hypoparathyroidism well.

The risk of central nodal metastasis based on prognostic factors of the differentiated thyroid carcinoma: a systematic review and meta-analysis study

BACKGROUND AND AIM

Despite improving the 10-year disease-free-survival, prophylactic central neck dissection (pCND) in differentiated thyroid carcinoma (DTC) should only be considered in patients with high risk factors for lymph node (LN) metastasis due to the increases in the risk of postoperative complications. Our aim was to identify the risk factors for central lymph node metastasis (CLNM) in DTC.

METHOD

We searched PubMed, Scopus, Web of science, Cochrane library for eligible studies from inception to November 1, 2021 and a systematic review and meta-analysis were carried out to identify the risk factors for CLNM in DTC.

RESULTS

We included 41 studies with total of 27,741 patients in this study. The pooled results in this meta-analysis showed that these risk factors were significantly associated with CLNM: age < 45 years (odds ratio (OR) 1.64, 95% confidence interval (CI) 1.34-1.99, p < 0.00001), male sex (OR 1.73, 95% CI 1.54-1.93, p < 0.00001), multifocality (OR 1.87, 95% CI 1.59-2.19, p < 0.00001), bilateral disease (OR 1.43, 95% CI 1.15-1.78, p < 0.001), capsular invasion (OR 1.67, 95% CI 1.10-2.54, p < 0.02), lymphovascular invasion (OR 4.89, 95% CI 2.76-8.66, p < 0.00001) and extra-thyroidal extension (OR 2.43, 95% CI 1.97-3.00, p < 0.00001). In addition, young age (< 45 years), male sex, multifocality, and extra-thyroidal extension were significantly associated with large-volume CLNM in clinically N0 DTC patients. However, the presence of Hashimoto's thyroiditis was not a predictors of large-volume CLNM.

CONCLUSION

Young age (< 45 years), male sex, bilateral disease, multifocality, capsular invasion, lymphovascular invasion and extra-thyroidal extension are significantly associated with CLNM and pCND would be expected to have a higher yield in patients with these risk factors.

Nomogram based on preoperative conventional ultrasound and shear wave velocity for predicting central lymph node metastasis in papillary thyroid carcinoma

OBJECTIVE

To establish a nomogram for predicting cervical lymph node metastasis (CLNM) based on the preoperative conventional ultrasound (US) and shear wave velocity (SWV) features of papillary thyroid carcinoma (PTC).

METHODS

A total of 101 patients with pathologically confirmed thyroid nodules were enrolled. These patients were divided into the CLNM-positive (n = 40) and CLNM-negative groups (n = 61). All patients underwent the preoperative conventional US and shear wave elastography (SWE) evaluation, and the US parameters and SWV data were collected. The association between SWV ratio and CLNM was compared to assess the diagnostic efficacy of SWV ratio alone as opposed to SWV ratio in combination with the conventional US for predicting CLNM.

RESULTS

There were significant differences in shape, microcalcification, capsule contact, SWV mean, and SWV ratio between the CLNM-positive and CLNM-negative groups (P < 0.05). Logistic regression analysis showed that taller-than-wide shape, microcalcification, capsule contact, and SWV ratio > 1.3 were risk factors for CLNM; Logistic(P)=-6.93 + 1.647 * (microcalcification)+1.138 * (taller-than-wide-shape)+1.612 * (capsule contact)+2.933 * (SWV ratio > 1.3). The area under the curve (AUC) of the receiver operating characteristic (ROC) of the model for CLNM prediction was 0.87, with 81.19% accuracy, 77.5% sensitivity, and 85.25% specificity.

CONCLUSION

The nomogram based on conventional US imaging in combination with SWV ratio has the potential for preoperative CLNM risk assessment. This nomogram serves as a useful clinical tool for active surveillance and treatment decisions.

Evaluation of the role of prophylactic bilateral central neck lymph node dissection in patients with papillary thyroid carcinoma: a case controlled study

Thyroid cancer is the most common malignancy in the endocrine system. Papillary thyroid carcinoma (PTC) is the most common differentiated thyroid cancer. There are considerable discrepancies regarding the role and extent of prophylactic central lymph node dissection (PCLND) for patients with PTC. Our primary goal was the evaluation of CLN involvement based on the tumor features and staging on the eight version of the American Joint Committee on Cancer and also the TNM method. Our secondary aim was to evaluate the features of the CLNs with tumoral features and also features associated with the development of transient hypoparathyroidism. This prospective case-controlled study was performed among PTC patients. Total thyroidectomy and bilateral dissection of the CLNs of the central compartment of the neck was performed, and samples were sent for pathological evaluation. CLN involvement, tumoral features and transient hypoparathyroidism were cross-evaluated and analyzed with SPSS version 26.0. In this study, out of 61 patients, 11 (18%) were male, the average age was 37.3 ± 13.7 years, based on AJCC staging, 53 (86.9%) were stage I and 8 (13.1%) were stage II, and based on TNM staging, 39 patients (66.1%) were T1, including 13 (22.0%) T1a and 26 (44.1%) T1b, 15 patients (25.4%) were T2, and five patients (8.5%) were T3. Based on permanent pathology evaluation, the majority of patients (n = 48; 78.7%) had CLN involvement. None of the preoperative and tumor features had a significant association with CLN involvement. 75% of stage I and 100% of stage two cases, while 76.9% of T1, 86.7% of T2, and 80.0% of T3 cases had CLN involvement. There was no significant association between the involvement of CLN and the AJCC staging (P = 0.184) or TNM staging (P = 0.875). The involved to dissected CLN ratio was significantly higher in stage II patients compared to stage I (72.5 vs. 34.8%; P = 0.006), and also with higher T staging (0.009). There was a statistically significant association between the larger CLN size and older patients' age, higher postoperative thyroglobulin levels, and smaller tumor size. Higher postoperative thyroglobulin level was significantly associated with larger tumors size and thyroid capsule invasion. Also, 26 (44.8%) of patients developed transient hypoparathyroidism, which was significantly associated with vascular invasion (P = 0.048), bilateral location of tumor (P = 0.048) or on the right side (0.005), and larger size of the tumor (P = 0.016). Tumor features and staging were not associated with CLN involvement features. Therefore, full extent PCLND should be carried out to avoid reoperation or metastasis in PTC patients.

Radiologist versus Non-Radiologist Detection of Lymph Node Metastasis in Papillary Thyroid Carcinoma by Ultrasound: A Meta-Analysis

Papillary thyroid carcinoma (PTC) is the most common thyroid cancer worldwide and is known to spread to adjacent neck lymphatics. Lymph node metastasis (LNM) is a known predictor of disease recurrence and is an indicator for aggressive resection. Our study aims to determine if ultrasound sonographers’ degree of training influences overall LNM detection. PubMed, Embase, and Scopus articles were searched and screened for relevant articles. Two investigators independently screened and extracted the data. Diagnostic test parameters were determined for all studies, studies reported by radiologists, and studies reported by non-radiologists. The total sample size amounted to 5768 patients and 10,030 lymph nodes. Radiologists performed ultrasounds in 18 studies, while non-radiologists performed ultrasounds in seven studies, corresponding to 4442 and 1326 patients, respectively. The overall sensitivity of LNM detection by US was 59% (95%CI = 58–60%), and the overall specificity was 85% (95%CI = 84–86%). The sensitivity and specificity of US performed by radiologists were 58% and 86%, respectively. The sensitivity and specificity of US performed by non-radiologists were 62% and 78%, respectively. Summary receiver operating curve (sROC) found radiologists and non-radiologists to detect LNM on US with similar accuracy (p = 0.517). Our work suggests that both radiologists and non-radiologists alike detect overall LNM with high accuracy on US.

Truncal Ligation of Inferior Thyroid Artery Does Not Affect the Incidence of Hypocalcaemia After Central Compartment Lymph Node Dissection

Preserving all parathyroids with intact blood supply in situ is a desirable goal while performing total thyroidectomy (TT) and central compartment dissection (CCLND), but the same is not feasible in presence of bulky and/or matted lymph nodes in the central compartment. The aim of this study was to investigate the difference in incidence of postoperative hypocalcemia between the groups of papillary thyroid carcinoma (PTC) patients who had truncal ligation (TL) versus ligation of peripheral branches (PL) of inferior thyroid artery (ITA) during TT and CCLND. Retrospective review of prospectively kept data of PTC patients undergoing TT and CCLND. Patients were divided in two groups: Group 1-(n = 57) patients who had to undergo TL and Group 2-(n = 99) patients having PL. Clinico-pathologic profile, operative details and follow-up events were noted. Clinico-pathologic profile of both groups was comparable except for higher incidences of tumor multicentricity (p = 0.014) in Group 1. There was no significant difference in the number of parathyroids identified between the Groups (p = 0.556) but more parathyroids were auto-transplanted in Group 1 (p = 0.001). The incidence of temporary (77.2% vs 83.8, p = 0.304) and permanent hypocalcemia (7% vs 8.1%, p = 0.810) was not significantly different between the groups and neither was need for intravenous calcium. At discharge, Group 1 patients received lower dose of calcium (p = 0.001) but not of vitamin D (p = 0.769). TL of ITA during CCLND does not result in increased temporary or permanent hypocalcemia rate.

A Narrative Review of Preventive Central Lymph Node Dissection in Patients With Papillary Thyroid Cancer - A Necessity or an Excess

OBJECTIVE

This review article summarises the latest evidence for preventive central lymph node dissection in patients with papillary thyroid cancer taking into account the possible complications and risk of recurrence.

BACKGROUND

Papillary thyroid cancer is the most frequent histological variant of malignant neoplasms of the thyroid gland. It accounts for about 80-85% of all cases of thyroid cancer. Despite good postoperative results and an excellent survival rate in comparison with many other malignant diseases, tumor metastases to the cervical lymph nodes are frequent. Most researchers agree that the presence of obvious metastases in the lymph nodes requires careful lymph node dissection. It was suggested to perform preventive routine lymphadenectomy in all patients with malignant thyroid diseases referred to surgery.

METHODS

It was performed the literature review using the "papillary thyroid cancer", "central lymph node dissection", "hypocalcemia", "recurrent laryngeal nerve paresis", "metastasis", "cancer recurrence" along with the MESH terms. The reference list of the articles was carefully reviewed as a potential source of information. The search was based on Medline, Scopus, Google Scholar, eLibrary engines. Selected publications were analyzed and their synthesis was used to write the review and analyse the role of preventive central lymph node dissection in patients with papillary thyroid cancer.

CONCLUSIONS

The necessity of preventive central lymph node dissection in patients with differentiated papillary thyroid carcinoma is still controversial. There is much evidence that it increases the frequency of transient hypocalcemia. Due to the fact that this complication is temporary, its significance in clinical practice is debatable. It can also be assumed that an extant of surgery in the neck area is associated with an increased risk of recurrent laryngeal nerve injury. However, most studies indicate that this injury is associated more with thyroidectomy itself than with lymph node dissection. Recurrent laryngeal nerve dysfunction is also a temporary complication in the vast majority of cases. At the same time, a large amount of data shows that central lymph node dissection reduces the risk of thyroid cancer recurrence in two times.

Risk Factors for Central Lymph Node Metastases and Benefit of Prophylactic Central Lymph Node Dissection in Middle Eastern Patients With cN0 Papillary Thyroid Carcinoma

Background

Prophylactic central lymph node dissection (PCLND) for adult patients with papillary thyroid carcinoma (PTC) is still a matter of debate. Data on incidence, risk and benefits of PCLND in Middle Eastern patients is lacking. Therefore, we aimed to identify the incidence and predictive clinico-pathological and molecular marker of PCLND in adult patients with clinically node negative (cN0) Middle Eastern PTC.

Methods

This retrospective study included 942 adult Middle Eastern patients with cN0 PTC who underwent total thyroidectomy (TT) or TT+PCLND. Clinico-pathological associations of central lymph node metastasis (CLNM) were assessed. Multivariate analysis was performed using logistic regression and Cox proportional hazards model.

Results

213 patients underwent PCLND and 38.0% (81/213) had positive CLNM. Multivariate analysis demonstrated age ≤55 years (Odds Ratio (OR) = 7.38; 95% Confidence Interval (CI) = 1.59 – 34.31; p = 0.0108), tumor bilaterality (OR = 3.01; 95% CI = 1.01 – 9.21; p = 0.0483), lymphovascular invasion (OR = 2.92; 95% CI = 1.18 – 7.23; p = 0.0206) and BRAF mutation (OR = 3.24; 95% CI = 1.41 – 7.49; p = 0.0058) were independent predictors of CLNM in adult PTC. Furthermore, patients who underwent PCLND showed significant association with improved recurrence-free survival (RFS; p = 0.0379). Multivariate analysis demonstrated that PCLND was an independent predictor of improved recurrence-free survival.

Conclusions

cN0 Middle Eastern PTC patients treated with PCLND showed a significantly better prognosis. PCLND was effective in improving RFS in Middle Eastern PTC patients and should be encouraged for patients with potential risk factors for CLNM.

Prophylactic Central Neck Dissection for cN1b Papillary Thyroid Carcinoma: A Systematic Review and Meta-Analysis

Background

The value of prophylactic central neck dissection (PCND) for papillary thyroid carcinoma (PTC) with clinically evident lateral cervical lymph node metastases (cN1b) remains unclear. Therefore, a systematic review and meta-analysis was conducted to assess the efficacy and safety of PCND.

Methods

A comprehensive systematic search was conducted on PubMed, Web of Science, Cochrane library and Embase databases up to September 2021 to identify eligible studies. Controlled clinical trials assessing therapeutic effects and safety of PCND for cN1b PTC patients were included. The risk of bias for each cohort study was assessed using the Newcastle-Ottawa Scale (NOS). The primary outcomes were indexes related to the locoregional recurrence (LRR) and surgical complications. Review Manager software V5.4.0 was used for statistical analysis. A fixed effects model was adopted for the data without heterogeneity, otherwise a random effects model was used.

Results

We included 4 retrospective cohort studies, which comprised 483 PTC patients. There was no statistically significant difference in the central neck recurrence (CNR) (10.2% vs. 3.8%, relative risk (RR) = 1.82; 95%CI 0.90–3.67; P = 0.09), lateral neck recurrence (LNR) (5.1% vs. 7.7%, RR = 0.47; 95% CI 0.13–1.74; P = 0.26), and overall recurrence (OR) (18.9% vs. 16.9%, RR = 0.77; 95%CI 0.34–1.76; P = 0.54), between LND + PCND group and LND group. Simultaneously, PCND increased the risk of permanent hypoparathyroidism (11.4% vs. 4.5%, RR = 2.70, 95%CI 1.05–6.94; P = 0.04) and overall complications (17.0% vs. 5.3%, RR = 3.28; 95%CI 1.37–7.86; P = 0.008).

Conclusions

This meta-analysis showed that PCND did not have any advantage in preventing LRR for cN1b PTC. Meanwhile, PCND may result in the increased rate of surgical complications. However, the current evidence is limited and more clinical trials are still needed to further clarify the true role of PCND.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/, CRD42021281825.

A Proposed Heterogeneous Ensemble Algorithm Model for Predicting Central Lymph Node Metastasis in Papillary Thyroid Cancer

Purpose

To develop a heterogeneous ensemble algorithm model to precisely predict central lymph node metastasis (CLNM), which can provide a reference value on controversial topics of performing prophylactic central lymph node dissection for patients with papillary thyroid cancer (PTC).

Methods

The study included patients with PTC who underwent an initial thyroid resection in a single-center medical institution between January 2014 and December 2018. A total of 18 variables, including clinical features and ultrasound (US) features, were used in the univariate analysis, multivariate analysis, and feature selection and were also used to develop a heterogeneous ensemble model based on five basic machine learning models, including extreme gradient boosting, k-nearest neighbors, random forest, gradient boosting, and AdaBoost. Moreover, a partial dependent plot was used to explain the heterogeneous ensemble model.

Results

The area under the receiver operating characteristic curve of the heterogeneous ensemble algorithm model was 0.67, which is significantly better than that of the basic machine models in predicting CLNM. All machine learning models performed better than US. Based on multivariate analysis and receiver operating characteristic curve analysis, age ≤33 years, tumor size ≥0.8 cm, US-suspected CLNM, and microcalcification were risk factors for CLNM, and anti-thyroid peroxidase antibody and serum thyroglobulin levels were favorable factors for CLNM.

Conclusion

The proposed heterogeneous ensemble algorithm model may be optimal tool to predict CLNM by integrating clinical and US features.

The Predictive Value of ACR TI-RADS Classification for Central Lymph Node Metastasis of Papillary Thyroid Carcinoma: A Retrospective Study

BACKGROUND

The aim of this retrospective study was to evaluate the risk factors for central lymph node metastasis (CLNM) in papillary thyroid carcinoma (PTC), according to the guidelines of the 2017 Thyroid Imaging Report and Data System (TI-RADS) published by the American College of Radiology (ACR).

METHODS

This study included a retrospective analysis of 844 patients with PTC who were pathologically diagnosed, treated with central lymph node dissection, and divided into CLNM and nonmetastatic groups. Univariate and multivariate analyses were performed to determine the relationship between the TI-RADS score and CLNM.

RESULTS

Among 844 patients, 439 developed CLNM, with a metastasis rate of 52% and a TI-RADS score of 9.42 ± 2.262, which were higher than those of the non-CLNM group (P < 0.05). Univariate analysis demonstrated that the sex, location, maximum diameter of the nodule, multifocality, margin, shape, calcification, and TI-RADS score were related to CLNM (P < 0.05 for all). However, multivariate logistic regression analysis demonstrated that female, maximum diameter of the nodule, multifocality, a taller-than-wide shape, and high TI-RADS score were the independent risk factors for CLNM (P < 0.05 for all).

CONCLUSION

The TI-RADS score combined with sex, nodule size, shape, and multifocality has a certain predictive effect on CLNM, which can provide a reference to the clinicians for further treatment strategies.

Real-World Evidence on the Sensitivity of Preoperative Ultrasound in Evaluating Central Lymph Node Metastasis of Papillary Thyroid Carcinoma

INTRODUCTION

Guidelines for prophylactic dissection in clinical central negative node (cN0) of papillary thyroid carcinoma vary among different countries due to the uncertainty on the benefit of dissection. The Chinese guidelines recommend prophylactic central compartment lymph node dissection (pCLND) under professional technology. Preoperative ultrasound (US) evaluation of central lymph node determines the surgical strategy used. Sensitivity differs significantly when US is conducted by different physicians even in diverse hospitals. In this study, the aim was to explore why the Chinese guidelines were different from the America Thyroid Association (ATA) guidelines through the real-world evidence on the preoperative diagnosis of cN0.

METHODS

Preoperative US and surgical pathology data for 1,015 patients with PTC attending 13 Grade-A tertiary hospitals in 2017 were collected. A retrospective analysis using US assessment of CLNM was the conducted to explore the benefits of this approach in China. US physicians in our hospital were trained on scanning the thyroid gland and its regional lymph nodes in normalization. Data of 1,776 patients were collected under the same condition from 2012 to 2017, whose ultrasonography was performed by diverse physicians and doctors. Further, data of 339 patients evaluated by the same sonographer and operated by the same surgical team was collected between 2015 and 2017. In this set of data, US combined CT versus US alone was compared. Patients were grouped into metastasis group and non-metastasis group based on postoperative pathological diagnosis of CLNM. Diagnostic efficacy of US was evaluated.

RESULTS

A total of 925 patients who underwent preoperative ultrasonography in central lymph node, including 825 cases who underwent thyroidectomy and central lymph node dissection were included in this study. The sensitivity of ultrasonography in detecting CLNM was 23.18%, with occult metastasis rate of 40.8%. Data for 1,776 patients comprising paired ultrasonic report and pathological report were collected in our hospital, whose physicians underwent standardized training. The sensitivity was 37.58%. Furthermore, specialized evaluation showed high sensitivity in US/CT (84.58%) than US (58.21%) alone.

CONCLUSION

Although the sensitivity of US could be enhanced by standardized training and combination with CT, the prevalence of low sensitivity of US in real-world multicenter data and the high occult metastasis rate indicated that the Chinese guidelines were based on the current conditions.

Prediction of central compartment nodal metastases in papillary thyroid cancer using TI-RADS score, blood flow, and multifocality

BACKGROUND

The relationship between the American College of Radiology (ACR) Thyroid Imaging Reporting and Data System (TI-RADS) and the risk of lymph node metastases in papillary thyroid cancer (PTC) could improve the detection rate of lymph node metastases in thyroid cancer and provide a scientific basis for clinical diagnosis.

PURPOSE

To evaluate the risk of lymph node metastases of PTC associated with the score from ACR TI-RADS adjusted for other correlative factors.

MATERIAL AND METHODS

A total of 560 patients with pathologically confirmed PTC were included in the study and classified into a metastases group and a non-metastases group. Clinical and pathological manifestations of the patients were collected.

RESULTS

The median TI-RADS score was 13 (p₂₅-p₇₅ = 11-14) among the patients with lymph node metastases, higher than those without metastases 9 (8-10) (P < 0.001). Multiple logistic regression indicated that TI-RADS score (odds ratio [OR] = 2.204), male sex (OR = 2.376), multifocality (OR = 4.170), and rich blood flow (OR = 3.656) were risk factors for lymph node metastases in patients with thyroid carcinoma. Some related factors such as TI-RADS score, age(<45years old), male, multifocality and rich blood flow were related to lymph node metastases in the central area of the neck which could provide therapeutic strategy for further treatment.

CONCLUSION

it is not just the TI-RADS score but also multifocality, blood flow, and sex that influence the prediction of the risk of PTC central lymph node metastases.

Central lymph node dissection and permanent hypoparathyroidism after total thyroidectomy for papillary thyroid cancer: population-based study

BACKGROUND

Papillary thyroid cancer is treated with total/near-total thyroidectomy (TT) with or without central lymph node dissection (CLND), depending on risk factors and tumour size. Balancing the risk of disease recurrence and surgical morbidity remains a challenge. A population-based nationwide study was undertaken to evaluate the risk of permanent hypoparathyroidism associated with CLND.

METHOD

Data on patients with stage pT1-3 papillary thyroid cancer, who underwent TT with or without CLND between 1 July 2004 and 30 June 2014 were retrieved from the Scandinavian Quality Register for Thyroid, Parathyroid and Adrenal Surgery. Drug use was ascertained by cross-linking with the Swedish Prescribed Drug Register. Permanent hypoparathyroidism was defined as treatment with active D vitamin or oral calcium drugs for more than 6 months after surgery. Data were analysed separately for all patients and those who underwent TT + CLND. Univariable and multivariable logistic regression analyses were done, yielding odds ratios (ORs) with 95 per cent confidence intervals.

RESULTS

A total of 722 patients were included in the study. Permanent hypoparathyroidism was more common in the TT + CLND group than the TT group: 30 of 265 patients (6·6 per cent) versus six of 457 (2·3 per cent) (P = 0·011). In multivariable logistic regression analysis, CLND was a risk factor for permanent hypoparathyroidism (OR 3·74, 95 per cent c.i. 1·46 to 9·59, based on use of combined therapy 6 months after surgery). In patients who had TT + CLND, node negativity was associated with a risk of permanent hypoparathyroidism (OR 3·08, 1·31 to 7·25).

CONCLUSION

CLND is an independent risk factor for permanent hypoparathyroidism. Node negativity is associated with a higher risk of permanent hypoparathyroidism.

Primary study of identification of parathyroid gland based on laser-induced breakdown spectroscopy

The identification and preservation of parathyroid glands (PGs) is a major issue in thyroidectomy. The PG is particularly difficult to distinguish from the surrounding tissues. Accidental damage or removal of the PG may result in temporary or permanent postoperative hypoparathyroidism and hypocalcemia. In this study, a novel method for identification of the PG was proposed based on laser-induced breakdown spectroscopy (LIBS) for the first time. LIBS spectra were collected from the smear samples of PG and non-parathyroid gland (NPG) tissues (thyroid and neck lymph node) of rabbits. The emission lines (related to K, Na, Ca, N, O, CN, C₂, etc.) observed in LIBS spectra were ranked and selected based on the important weight calculated by random forest (RF). Three machine learning algorithms were used as classifiers to distinguish PGs from NPGs. The artificial neural network classifier provided the best classification performance. The results demonstrated that LIBS can be adopted to discriminate between smear samples of PG and NPG, and it has a potential in intra-operative identification of PGs.

A Randomized Controlled Clinical Trial: No Clear Benefit to Prophylactic Central Neck Dissection in Patients With Clinically Node Negative Papillary Thyroid Cancer

OBJECTIVE

The aim of this prospective randomized-controlled trial was to evaluate the risks/benefits of prophylactic central neck dissection (pCND) in patients with clinically node negative (cN0) papillary thyroid cancer (PTC).

BACKGROUND

Microscopic lymph node involvement in patients with PTC is common, but the optimal management is unclear.

METHODS

Sixty patients with cN0 PTC were randomized to a total thyroidectomy (TT) or a TT+ pCND. All patients received postoperative laryngoscopies and standardized radioiodine treatment. Thyroglobulin (Tg) levels and/or neck ultrasounds were performed at 6 weeks, 6 months, and 1 year.

RESULTS

Tumors averaged 2.2 ± 0.2 cm and 11.9% had extra-thyroidal extension. Thirty patients underwent a pCND and 27.6% had positive nodes (all ≤6 mm). Rates of postoperative PTH < 10 (33.3% vs 24.1%, P = 0.57) and transient nerve dysfunction (13.3% vs 10.3%, P = 1.00) were not significantly different between groups. Six weeks after surgery, both TT and TT + pCND were equally likely to achieve a Tg < 0.2 (54.5% vs 66.7%, P = 0.54) and/or a stimulated Tg (sTg) <1 (59.3% vs 64.0%, P = 0.78). At 1 year, rates of Tg < 0.2 (88.9% vs 90.0%, P = 1.00) and sTg < 1 (93.8% vs 92.3%, P = 1.00) remained similar between groups. Neck ultrasounds at 1 year were equally likely to be read as normal (85.7% in TT vs 85.1% in pCND, P = 1.00).

CONCLUSIONS

cN0 PTC patients treated either with TT or TT + pCND had similar complication rates after surgery. Although microscopic nodes were discovered in 27.6% of pCND patients, oncologic outcomes were comparable at 1 year.

Infiltration of nanocarbon suspension into the tracheal cavity during surgical treatment of papillary thyroid carcinoma: a case report

Cervical lymph node metastasis in patients with differentiated thyroid cancer affects postoperative recurrence and survival. Hypoparathyroidism is caused by parathyroid gland injury during thyroidectomy. Carbon nanoparticles can trace stained lymph nodes, aiding in thorough dissection of lymph nodes in the operation area. To reduce postoperative occurrence of hypoparathyroidism, the parathyroid glands and their functions (identified by negative imaging induced by carbon nanoparticles) are retained in situ. However, the safety and adverse effects of nanocarbon suspension in thyroid surgery have rarely been evaluated. In this report, we describe a patient with thyroid cancer who had carbon secretions in the trachea caused by nanocarbon suspension when tracheal intubation was performed under general anesthesia, and the inflatable balloon surface of the tracheal tube was covered with these secretions. The patient recovered without fever, cough, phlegm production, chest pain, hoarseness, or hypocalcemia-induced convulsions. No consensus has yet been reached on the most appropriate injection site, depth, dose, or waiting time for nanocarbons in thyroid cancer surgery. We believe that nanocarbon suspension is safe for use in thyroid cancer surgery, but the most appropriate injection depth should be based on the thickness of the thyroid gland tissue to avoid deep injection into the trachea.

Predictors and a Prediction Model for Central Cervical Lymph Node Metastasis in Papillary Thyroid Carcinoma (cN0)

OBJECTIVES

To screen out the predictors of central cervical lymph node metastasis (CLNM) for papillary thyroid carcinoma (PTC) and establish a prediction model to guide the operation of PTC patients (cN0).

METHODS

Data from 296 PTC patients (cN0) who underwent thyroid operation at the Second Affiliated Hospital of Chongqing Medical University were collected and retrospectively analyzed. They were divided into two groups in accordance with central CLNM or not. Their information, including ultrasound (US) features, BRAF^V600E status, and other characteristics of the two groups, was analyzed and compared using univariate and multivariate logistic regression analyses, and the independent predictors were selected to construct a nomogram. The calibration plot, C-index, and decision curve analysis were used to assess the prediction model's calibration, discrimination, and clinical usefulness.

RESULTS

A total of 37.8% (112/296) of PTC patients had central CLNM, and 62.2% (184/296) did not. The two groups were compared using a univariate logistic regression analysis, and there were no significant differences between the two groups in sex, aspect ratio, boundary, morphology, hypoechoic nodule, thyroid peroxidase antibody, or tumor location (P>0.05), and there were significant differences between age, tumor size, capsule contact, microcalcifications, blood flow signal, thyroglobulin antibodies (TgAb), and BRAF gene status (P<0.05). A multivariate logistic regression analysis was performed to further clarify the correlation of these indices. However, only tumor size (OR=2.814, 95% Cl=1.634~4.848, P<0.001), microcalcifications (OR=2.839, 95% Cl=1,684~4.787, P<0.001) and TgAb (OR=1.964, 95% Cl=1.039~3,711, P=0.038) were independent predictors of central CLNM and were incorporated and used to construct the prediction nomogram. The model had good discrimination with a C-index of 0.715. An ROC curve analysis was performed to evaluate the accuracy of this model. The decision curve analysis showed that the model was clinically useful when intervention was decided in the threshold range of 16% to 80%.

CONCLUSION

In conclusion, three independent predictors of central CLNM, including tumor size (> 1.0 cm), US features (microcalcifications), and TgAb (positive), were screened out. A visualized nomogram model was established based on the three predictors in this study, which could be used as a basis of central cervical lymph node dissection (CLND) for PTC patients (cN0).

Synergic effects of histology subtype, lymph node metastasis, and distant metastasis on prognosis in differentiated thyroid carcinoma using the SEER database

Background

Differentiated thyroid carcinoma (DTC) is the most common clinical type of thyroid carcinoma. There are rare reports on the synergic effects of the different clinicopathological risk factors on the prognosis of it.

Methods

We retrospectively reviewed data on 86,032 DTC patients from the Surveillance, Epidemiology, and End Results (SEER) database. Univariate and multivariate Cox regression analyses were conducted to evaluate the correlation between clinicopathological factors and the prognosis of DTC. Relative excess risk (RERI) of synergic effect, attributable proportion (AP) of synergic effect, and synergy index (SI) were calculated to assess synergic effects. Kaplan-Meier analyses with log-rank tests was used to plot the survival curve affected by different risk factors.

Results

Histology subtype, lymph node metastasis (LNM) status, and distant metastasis (DM) were independent risk factors for cancer-specific survival (CSS) and all-cause survival (ACS) in the multivariate analysis (all, P<0.001). Patients' age at diagnosis, sex, extrathyroidal extension, and radiation also influenced prognosis (all, P<0.001). The cancer-specific mortality (CSM) and all-cause mortality (ACM) rates per 1,000 person-years were higher in patients with follicular thyroid carcinoma (FTC) and in those with N1 stage and M1 stage disease. Furthermore, we observed a significant synergic effect between histology subtype and N stage, as well as histology subtype and M stage for the CSM of DTC (RERI =48.806, AP =0.853, SI =7.565; RERI =37.889, AP =0.430, SI =1.771, respectively). However, no synergic effect was observed in the case of the N stage and M stage for the CSM of DTC (RERI =7.928, AP =0.084, SI =1.093).

Conclusions

Patients with histology subtype of FTC and N1 stage, histology subtype of FTC and M1 stage had significant additive synergic effects on DTC prognosis for CSM.

Is a Prophylactic Central Compartment Neck Dissection Required in Papillary Thyroid Carcinoma Patients with Clinically Involved Lateral Compartment Lymph Nodes?

BACKGROUND

The 2015 American Thyroid Association guidelines state that a prophylactic central compartment neck dissection (PCND) should be considered for patients with papillary thyroid carcinoma (PTC) and clinically involved lateral neck lymph nodes (cN1b). The purpose of our study was to determine the rate of central neck recurrence in select cN1b patients, with no evidence of clinically involved central compartment lymph nodes, treated without a PCND.

METHODS

After institutional review board approval, adult PTC patients with cN1b disease who were treated with a total thyroidectomy and lateral neck dissection were identified from an institutional database of 6259 patients who underwent initial surgery for well-differentiated thyroid carcinoma from 1986 to 2015. Patients with gross extrathyroidal extension, distant metastases, or no preoperative imaging were excluded. Patients with evidence of clinically involved central compartment lymph nodes, on preoperative imaging or intraoperative evaluation, also were excluded. A total of 152 cN1b patients were included and categorized into non-PCND and PCND groups. Central neck recurrence-free probability (CNRFP) was calculated using the Kaplan-Meier method and log-rank tests.

RESULTS

One hundred three patients (67.8%) did not have a PCND. With a median follow-up of 65 months, the 5- and 10-year CNRFP was 98.4% in the non-PCND group and 93.6% in the PCND group (p = 0.133).

CONCLUSIONS

Select PTC patients with cN1b disease but no evidence of clinically involved central compartment lymph nodes, on preoperative imaging and intraoperative evaluation, appear to have a low rate of central neck recurrence. These patients may not require or benefit from a PCND.

Prophylactic lymph node dissection in clinically N0 differentiated thyroid carcinoma: example of personalized treatment

Considering the 'differentiated thyroid carcinoma (DTC) epidemic', the indolent nature of DTC imposes a treatment paradigm shift toward elimination of recurrence. Lymph node metastases in cervical compartments, encountered in 20-90% of DTC, are the main culprit of recurrent disease, affecting 5-30% of patients. Personalized risk-stratified cervical prophylactic lymph node dissection (PLND) at initial thyroidectomy in DTC with no clinical, sonographic or intraoperative evidence of lymph node metastases (clinically N0) has been advocated, though not unanimously. The present review dissects the controversy over PLND. Weighing the benefit yielded from PLND up against the PLND-related morbidity is so far hampered by the inconsistent profit yielded by PLND and the challenging patient selection. Advances in tailoring PLND are anticipated to empower optimal patient care.

Meta-analysis of risk factors for CCLNM in patients with unilateral cN0 PTC

BACKGROUND

In patients with papillary thyroid cancer (PTC) with clinical negative central lymph nodes (cN0), the use of prophylactic central lymph node dissection remains controversial. Contralateral central lymph node metastasis (CCLNM) occurs in 3.88–30.63% of patients with cN0 PTC. Therefore, the present meta-analysis aimed to obtain evidence for CCLNM risk factors in unilateral cN0 PTC.

MATERIALS AND METHODS

Relevant studies were identified in the PubMed, SCIE, and Wanfang databases up to Oct 31, 2019. The included patients had undergone lobectomy or total thyroidectomy with bilateral central lymph node dissection and were diagnosed pathologically with PTC. Revman 5.3 software was applied for statistical analysis.

RESULTS

Thirteen studies comprising 2449 patients were included. The factors associated with increased CCLNM risk in patients with cN0 disease were: age <45 years (odds ratio (OR) = 1.89, 95% CI = 1.43–2.49, P < 0.00001), male sex (OR = 1.67, 95% CI = 1.24–2.24, P = 0.0007), extrathyroidal extension (OR = 1.63; 95% CI = 1.17–2.28; P = 0.004), tumor size ≥1 cm (OR = 2.63, 95% CI 1.85–3.74, P < 0.00001), lymphovascular invasion (OR = 4.27, 95% CI = 2.47–7.37, P < 0.00001), and ipsilateral central lymph node metastasis (OR = 11.42, 95% CI = 5.25–24.86, P < 0.00001). However, no association was found for capsular invasion, multifocality, or Hashimoto thyroiditis.

CONCLUSION

The meta-analysis identified that age <45 years, tumor ≥1 cm, male sex, lymphovascular invasion, extrathyroidal extension, and ipsilateral central lymph node metastasis are related to CCLNM in patients with unilateral CN0 PTC. These factors should influence the use of prophylactic central lymph node dissection in this group of patients.

BAG5 promotes invasion of papillary thyroid cancer cells via upregulation of fibronectin 1 at the translational level

Papillary thyroid cancer (PTC), the most common thyroid malignancy, has a strong propensity for neck lymph node metastasis, which will increase the risk of local recurrence and decrease the survival in some high-risk groups. Hence, it is essential to set up a reliable biomarker to predict lymph node metastasis. BAG5 is a unique member of the BAG cochaperone family because it consists of more than one BAG domain, which acts as modulator of chaperone activity. In this study, we found that expression of BAG5 was significantly increased in PTC cells and tissues. Neither overexpression nor downregulation of BAG5 altered the proliferation of PTC cells. On the contrary, overexpression of BAG5 significantly promoted, while knockdown of BAG5 significantly decreased migration and invasion of PTC cells. Along with this, fibronectin 1 (FN1) was significantly increased and decreased in cells that overexpress or downregulate BAG5, respectively. Mechanistically, we found that BAG5 modulated FN1 expression at the translational level and promoted invasion via suppression of miR-144-3p, which targeted the 3' untranslational region (UTR) of FN1 transcript. This study suggests that BAG5 is an important regulator of migration and invasion in PTC cells and may represent a novel therapeutic target for intervening in PTC progression.

Positive central lymph-nodes are underdiagnosed in patients with Bethesda V cytology in an endemic goiter region

Background

Fine needle aspiration (FNA) is a significant diagnostic procedure for detecting malignancy in patients with nodular thyroid disease. A high proportion of patients with cytological diagnosed follicular neoplasia (Bethesda IV and V) ultimately have thyroid cancer. The aim of this study was to evaluate the incidence of preoperatively undiagnosed central lymph node metastasis in patients with multinodular goiter (MNG).

Methods

Patients who underwent FNA and were classified as Bethesda IV/V were included. Applying a radical approach, all patients underwent (hemi)thyroidectomy and prophylactic unilateral central neck dissection.

Results

During our study period 2009-2013, 60 patients (19.7%) were classified as Bethesda IV and 21 (6.9%) Bethesda V. Final histopathological results revealed malignancy in 35 (43.2%) of 81 Bethesda IV/V nodules. Of the nodules classified as Bethesda IV, 20 (33.3%) showed malignancy in the final histology. Ten patients (16.7%) had papillary micro-carcinoma (mPTC, <10 mm), 4 (6.6%) PTC and 6 (10%) follicular thyroid cancer. Fifteen of 21 (71.4%) Bethesda V nodules were revealed as PTC of whom seven (33.3%) patients also had lymph-node metastases.

Conclusions

While 33.3% of the patients with PTC, preoperatively classified as Bethesda V, had previously undetected positive lymph-nodes, only one patient with Bethesda IV had lymph-node metastasis.

Effect of prophylactic central neck dissection on the surgical outcomes in papillary thyroid cancer: experience in a single center

PURPOSE

Morbidity due to papillary thyroid carcinoma (PTC) is increased mostly due to lymph node (LN) metastases, which lead to reoperations and complications associated with these operations. The aim is to compare the outcomes of PTC having total thyroidectomy and prophylactic central lymph node dissection (TT + PCND) with patients having total thyroidectomy (TT) alone.

METHODS

This study is a retrospective cohort analysis of 358 PTC patients that were operated by a single surgeon in a single center. Data about the patients were extracted from the medical records.

RESULTS

Of the patient cohort, 258 patients had TT + PCND (42.5 ± 11.3 years) and 100 patients (41.2 ± 11.9 years) had only TT. Total number of LN extracted in the TT + PCND group was 8.1 ± 6.9. The mean number of metastatic LN were 2.2 ± 1.9. Percentage of patients that had RAI were less in the TT + PCND group compared to the TT group. Seven patients (2.7%) in the TT + PCND group and 19 (19.0%) in TT group had recurrent disease (p < 0.0001). Of the complications, only transient hypoparathyroidism was increased in TT + PCND group compared to TT group (26.7% vs 10%, p < 0.0001).

CONCLUSION

TT + PCND performed by an experienced surgeon seems to decrease the number of LN recurrences, and the need for reoperations.

BRAF mutation analysis by ARMS-PCR refines thyroid nodule management

BACKGROUND

Fine-needle aspiration (FNA) of thyroid nodules leads to nearly 25% indeterminate nodules, while BRAF^V600E mutation helps to predicting papillary thyroid carcinoma (PTC). However, the clinical validity and utility of the BRAF^V600E mutation detected using preoperative FNA samples in a large cohort were rarely reported.

AIM

To explore the clinical significance of the BRAF^V600E mutation on preoperative diagnosis and decision-making in a large FNA cohort in China.

DESIGN

This was a prospective study of BRAF^V600E mutation analysis using an amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) in FNA samples.

PATIENTS

The study involved 2640 samples from 2307 patients undergoing FNA procedures in a Chinese medical centre.

RESULTS

A high mutation rate of 86.7% was found in the PTC population. For indeterminate thyroid nodules, the malignant rate of BRAF^V600E+ and BRAF^V600E- was 87.8% and 39.5% in the Bethesda System for Reporting Thyroid Cytopathology (BSRTC) III, and 88.2% and 31.8% in the BSRTC IV, respectively. A cost-effective diagnostic model combining both BSRTC grading and BRAF^V600E mutation status showed the highest sensitivity of 82.9% and specificity of 85.4%. Central lymph node metastasis (CLNM) was independent of the BRAF mutation status and accounted for 34.2% of the patients with PTC. C_T values of BRAF^V600E of patients with PTMC were significantly lower in young patients and patients with CLNM.

CONCLUSIONS

The combined analysis of cytological results and BRAF^V600E mutation is highly recommended in BRAF^V600E high-prevalence regions, including China. Prophylactic central neck dissection should be performed in selected patients without regard to the BRAF mutation status.

Risk factors of post-surgery complications in children with thyroid cancer

INTRODUCTION

Thyroid cancer in children is a hot topic because of the large clinical heterogeneity and the risk of severe complications. We aimed to study 1. The frequency, 2. Etiology, and 3. Risk factors of post-surgery complications of thyroid cancer.

MATERIAL AND METHODS

A retrospective analysis including risk factors for post-surgery complications of patients treated for thyroid malignancies in years 2006-2018 was performed.

RESULTS

Over a period of 12 years 22 patients with thyroid malignancy (68% female; 12.6 ± 4.0 years of age, median follow-up 6 years) were identified. Histologically, 12 (55%) patients had papillary carcinoma. Six patients (27.3%) had multiple endocrine neoplasia type 2 (MEN2) syndrome, 3 (13.7%) patients had medullary carcinoma and 1 patient had follicular carcinoma. Neck lymph node metastases were diagnosed in 8 (36.4%), distant metastases in 6 (27.3%), and both locations were involved in 4 (18.2%) patients. Six (27.3%) children had surgical complications: 1 child had unilateral vocal cord paralysis and transient hypoparathyroidism and 5 had transient hypoparathyroidism. The higher risk of surgery complications in forward stepwise logistic regression was associated in with distant metastases (R2 = 0.584, OR 52.63, p = 0.010).

CONCLUSIONS

Postoperative complications were significantly associated with presence of distant metastases. Favorable results were observed in with children with MEN2 syndrome.

Reduction in postoperative hypoparathyroidism following carbon nanoparticle suspension injection combined with parathyroid gland vasculature preservation

Objective

We evaluated the effectiveness of carbon nanoparticle suspension injection combined with parathyroid gland vasculature preservation to identify and preserve the parathyroid gland to reduce postoperative hypoparathyroidism following thyroidectomy.

Material and Methods

Fifty patients with thyroid tumors received carbon nanoparticle suspension injection combined with parathyroid gland vasculature preservation (group A). Serum calcium and PTH levels were recorded and compared with those of 50 control patients who underwent a standard thyroidectomy procedure (group B).

Results

The serum calcium level in group A was significantly higher than that in group B at day 1 (2.20 ± 0.02 vs 2.11 ± 0.03 mmol/L) and day 30 (2.27 ± 0.01 vs 2.21 ± 0.02 mmol/L) after surgery. The PTH level in group A was also significantly higher than that in group B at day 1 (33.5 ± 2.36 vs. 25.31 ± 2.98 pg/mL) after surgery. The incidence of hypoparathyroidism was significantly higher in group B than in group A at day 1 after surgery (19 vs. 7 patients).

Conclusion

When combined with parathyroid gland vasculature preservation, carbon nanoparticle suspension injection can effectively reduce the incidence of temporary parathyroidism following thyroid surgery.

Right posterior paratracheal lymph nodes metastasis is one of the predictive factors in right-sided papillary thyroid carcinoma

BACKGROUND

Lymph nodes in the right paratracheal region are separated as anterior and posterior on the basis with right recurrent laryngeal nerve. Dissection of the right posterior paratracheal lymph nodes is sometimes overlooked during a central neck dissection. Therefore, this study was designed to assess the clinicopathologic risk factors and prognostic implication for recurrence related to the presence of right posterior paratracheal lymph nodes metastasis in patient with right-sided papillary thyroid carcinoma.

METHODS

Records from 763 patients with papillary thyroid carcinoma who underwent total thyroidectomy with central neck dissection, including the right posterior paratracheal lymph nodes, between January 2007 and March 2015 were reviewed retrospectively.

RESULTS

Among 763 patients (120 men and 643 women; mean age 49.04 years) with right-sided papillary thyroid carcinoma, 127 exhibited right posterior paratracheal lymph nodes metastases. In multivariate analysis, central-compartment lymph nodes metastases (odds ratio 5.203; 95% confidence interval, 2.864-9.453) and lateral cervical lymph nodes metastases (odds ratio 3.668; 95% confidence interval, 2.375-5.667) were independently correlated with right posterior paratracheal lymph nodes metastases. Twenty-three patients (3.0%) showed loco-regional recurrence. The loco-regional recurrence rate was greater in the groups for males (P = .012), larger tumor size (>10 mm; P = .044), extrathyroidal extention (P = .002), and right posterior paratracheal lymph nodes metastasis (P < .001).

CONCLUSION

Right posterior paratracheal lymph nodes metastases are predictive factors of loco-regional recurrence, and these lymph nodes should be removed completely during a right central neck dissection in patients with right-sided papillary thyroid carcinoma with central or lateral cervical lymph node metastasis.

Parathyroid autotransplantation at a novel site for better evaluation of the grafted gland function: study protocol for a prospective, randomized controlled trial

Background

Hypoparathyroidism is one of the most common complications encountered in thyroidectomy. In addition to parathyroid in-situ preservation, parathyroid autotransplantation (PA) is another important remedial method for patients whose parathyroid glands have been removed. However, an accurate evaluation method for the function of a transplanted parathyroid is lacking. Our preliminary study indicated that patients with PA at novel sites near antecubital veins had higher serum concentrations of parathyroid hormone (PTH). Therefore, the main hypothesis is that a grafted site closer to the cephalic vein is more useful for better evaluation of transplanted parathyroid function. This study aims to confirm the more efficient and accurate evaluation system through a prospective, randomized controlled trial.

Methods

In total, 280 patients will be enrolled in this study and randomly divided into two groups: 140 patients with transplanted parathyroid glands in the traditional sites (group A) and the other 140 transplanted in the novel sites (group B), close to the antecubital veins. The serum concentration of PTH and calcium ion from both forearms will be measured and monitored regularly for 12 months. The primary outcome of this trial will be the survival of grafted glands, defined as the ratio of PTH between the grafted vs. the non-grafted forearms being no less than 1.5. The secondary outcome is hypoparathyroidism, defined as the PTH level from the non-grafted forearms being less than 15 pg/ml (normal range 15–65 pg/ml).

Discussion

Our results from this study should provide a more accurate method to evaluate the function of transplanted parathyroid glands by comparing PTH concentrations in both the grafted and non-grafted forearms following PA at novel sites. A better PTH measurement is helpful not only for the management of postoperative patients, but also for further identification of factors affecting PA success.

Trial registration

ClinicalTrials.gov, ID: NCT02906748. Registered on 16 March 2016.

Electronic supplementary material

The online version of this article (10.1186/s13063-019-3195-9) contains supplementary material, which is available to authorized users.

Role of ultrasonographic features and quantified BRAFV600E mutation in lymph node metastasis in Chinese patients with papillary thyroid carcinoma

The association between cervical lymph node metastasis (LNM) and ultrasonographic features as well as BRAF^V600E mutations in patients with papillary thyroid carcinoma (PTC) remained controversial. This study investigated the association between LNM and ultrasonographic features as well as BRAF^V600E mutation in Chinese patients with PTC. A total of 280 patients with PTC in China were included in this study. 108 had cervical lymph node metastasis, while 172 had not. Younger age (<45years) and several ultrasonographic features were significantly associated with cervical LNM (Ps < 0.05). The BRAF^V600E mutation was detected in 81.0% of patients with PTC (226/280). The status of BRAF^V600E mutation was not associated with cervical LNM. However, Ct values by PCR and intensity of reactions by immunohistochemistry (IHC) for BRAF^V600E expression had shown significant difference between group with and without LNM. Furthermore, an increased proportion of LNM was also found with the incremental intensity of IHC for BRAF^V600E expression from weak to strong reaction after adjusted potential confounders. Further studies are required to verify this association and explore the intrinsic mechanism.

Conventional Ultrasound, Immunohistochemical Factors and BRAFV600E Mutation in Predicting Central Cervical Lymph Node Metastasis of Papillary Thyroid Carcinoma

The study was aimed at evaluating the correlation between central cervical lymph node metastasis (CLNM) in papillary thyroid carcinoma (PTC) patients and ultrasound (US) features, immunohistochemical factors and BRAFV600E mutation. A total of 225 consecutive patients (225 PTCs) who had undergone surgery were included. All PTCs were pre-operatively analysed by US with respect to size, components, echogenicity, shape, margins, microcalcification, multiple cancers or not, internal vascularity and capsule contact or involvement. The presence of four immunohistochemical factors, including cytokeratin 19, human bone marrow endothelial cell 1, galectin-3 and thyroid peroxidase, and BRAFV600E mutation was also evaluated. Univariate and multivariate analyses were performed to identify the risk factors for central CLNM, and a risk model was established. Pathologically, 44% (99/225) of the PTCs had central CLNMs. Multivariate analysis revealed that size ≤10mm, microcalcification, internal vascularity, capsule contact or involvement and BRAFV600E mutation were independent risk factors for central CLNM. The risk score for central CLNM was calculated as follows: risk score = 1.5 × (if lesion size ≤10 mm) + 1.9 × (if microcalcification) + 0.8 × (if internal flow) + 3.0 × (if capsule contact or involvement) + 1.5 × (if BRAFV600E mutation). The rating result was divided into six stages, and the relevant risk rates of central CLNM were 0% (0/1), 0% (0/22), 7.4% (4/54), 48.6% (34/70), 71.2% (42/59) and 100% (19/19), respectively. In conclusion, PTC ≤10mm, microcalcification, internal vascularity, capsule contact or involvement and BRAFV600E mutation are risk factors for central CLNM. The risk model may be useful in treatment planning and management of patients with PTCs.

Retrospective analysis of prognostic factors in patients of papillary thyroid microcarcinoma

We performed a retrospective chart review of 245 patients with papillary thyroid microcarcinoma (PTMC) to define factors linked to central lymph node metastasis and thus prognosis. Univariate and multivariate analyses showed that being male (p < 0.001), age <45 years at diagnosis (p = 0.045), maximum tumor size > 5 mm (p = 0.030), multifocal tumor (p = 0.040) and tumor envelope invasion (p < 0.001) were all independent risk factors for central compartment lymph node metastasis. Unifocal lesions at the thyroid gland’s upper pole, middle and lower pole, had lymph node metastasis rates of 22.7%, 14.0% and 35.0%, respectively (p = 0.048). The rate of central lymph node metastasis was much higher when there was bilateral thyroid involvement than with multifocal unilateral lesions (58.6% vs 37.5%; p = 0.040). These results suggest that for patients at low risk of central lymph node metastasis, unilateral thyroid lobe and isthmus resection is sufficient. However, for patients at high risk of central lymph node metastasis, central lymph node dissection increases the likelihood of complete tumor excision.

Risk factors for central neck lymph node metastases in follicular variant vs. classic papillary thyroid carcinoma

PURPOSE

Histological variants of papillary thyroid carcinoma (PTC) have been advocated as possible risk factors for central neck nodal metastases (CNM). A lower incidence of CNM in follicular variant of papillary thyroid carcinoma (fvPTC) when compared with classic PTC (cPTC) has been observed. We aimed to compare risk factors for CNM in patients with fvPTC and cPTC.

METHODS

The medical records of 1737 patients with a diagnosis of cPTC or fvPTC were reviewed. Demographic, clinical and pathological findings were prospectively registered. Risk factors for CNM were evaluated by univariate and multivariate analysis in cPTC vs. fvPTC patients.

RESULTS

Six hundred and fifty-two patients (37.5%) had fvPTC. The diagnosis was incidental in 69.5% of the fvPTC and in 29.4% of the cPTC patients. Overall, 26.3% cPTC and 8.3% fvPTC patients showed CNM (p < 0.001). In both cPTC and fvPTC patients at univariate analysis age <45 years, nonincidental diagnosis, tumor size >5 mm, multifocality, angioinvasion and extracapsular invasion were risk factors for CNM. At multivariate analysis independent risk factors for CNM in both cPTC and fvPTC patients were age <45 years (p < 0.01), nonincidental diagnosis (p < 0.001), multifocality (p < 0.001) and extracapsular invasion (p < 0.001).

CONCLUSIONS

No differences were observed between cPTC and fvPTC with regard to risk factors of CNM. fvPTC seems associated with a lower incidence of CNM, presumably because of the higher rate of incidental diagnosis. With the exception of age, in patients with a preoperative diagnosis of PTC, no preoperatively available clinical parameter is a reliable predictor of CNM.

Predictive gene signatures of nodal metastasis in papillary thyroid carcinoma

BACKGROUND

Cervical lymph node metastases (LNM) in papillary thyroid carcinomas (PTCs) are common and develop in approximately 30-80% of PTCs. The presence of cervical LNM significantly increases the rate of locoregional recurrence in PTCs.

OBJECTIVE

To search for predictive gene signatures for nodal metastasis in PTCs.

METHODS

We used unsupervised clustering with unbiased manner to compare molecular profiles between PTCs with nodal metastasis and PTCs without nodal metastasis using mRNA-seq of TCGA data. Using gene ontology (GO) and logistic regression test, we generated 12-predictive genes for nodal metastasis in PTCs.

RESULTS

Unsupervised clustering of mRNA-seq (training set, N = 158) revealed that PTCs with nodal metastasis showed different gene expression patterns compared to PTCs without nodal metastasis. We generated 12 predictive genes and these gene signatures showed consistency for predicting nodal metastasis when we applied them to a validation set (N = 80). Based on multivariate analysis, these 12 predictive gene signatures showed more significant odds ratio compared to other variables.

CONCLUSIONS

These 12 gene signatures could be used to predict the chance of nodal metastasis in PTCs in preoperative evaluation using fine needle aspiration biopsy (FNAB) so that appropriate plan such as central neck dissection could be made.

Risk Factors for Central Neck Lymph Node Metastases in Micro- Versus Macro- Clinically Node Negative Papillary Thyroid Carcinoma

BACKGROUND

Tumor size has been advocated as possible risk factors for occult central lymph node metastases (CNM) in papillary thyroid carcinoma (PTC) patients. This prospective study evaluated factors that could identify patients at higher risk of occult CNM, especially comparing micro-PTC and macro-PTC.

METHODS

One hundred and eighty-six patients were recruited. All the patients had cN0 clinically unifocal PTC and underwent total thyroidectomy and bilateral prophylactic central neck dissection. Risk factors for occult CNM in micro- and macro-PTC patients were evaluated.

RESULTS

Eighty-two patients showed CNM. The rate of CNM did not differ among different sizes cut off (≤20 mm, ≤10 mm, ≤5 mm P = NS). Significantly more pN1a than pN0 patients had pT3 tumors (35/82 vs. 26/104) (P < 0.05), extracapsular invasion (35/82 vs. 22/104) (P < 0.01) and microscopic multifocal disease (50/82 vs. 47/104) (P < 0.05). Independent risk factors for CNM were extracapsular invasion and multifocality at multivariate analysis. Risk factors for CNM in 77 micro-PTC were extracapsular invasion (16/31 pN1 vs. 10/46 pN0, P < 0.05) and multifocality (21/31 pN1 vs. 16/46 pN0, P < 0.01). Among 109 macro-PTC, risk factors for CNM were angioinvasion (15/51 pN1 vs. 7/58 pN0, P < 0.05) and classic PTC at the final histology (PTC vs. tall cell variant vs. follicular variant PTC) (P < 0.05).

CONCLUSIONS

Risk factors for CNM can differ between micro- and macro-PTC, but no preoperatively known clinical parameter is predictor of CNM in cN0 clinically unifocal PTC.